887 research outputs found

    Low-Mach-number turbulence in interstellar gas revealed by radio polarization gradients

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    The interstellar medium of the Milky Way is multi-phase, magnetized and turbulent. Turbulence in the interstellar medium produces a global cascade of random gas motions, spanning scales ranging from 100 parsecs to 1000 kilometres. Fundamental parameters of interstellar turbulence such as the sonic Mach number (the speed of sound) have been difficult to determine because observations have lacked the sensitivity and resolution to directly image the small-scale structure associated with turbulent motion. Observations of linear polarization and Faraday rotation in radio emission from the Milky Way have identified unusual polarized structures that often have no counterparts in the total radiation intensity or at other wavelengths, and whose physical significance has been unclear. Here we report that the gradient of the Stokes vector (Q,U), where Q and U are parameters describing the polarization state of radiation, provides an image of magnetized turbulence in diffuse ionized gas, manifested as a complex filamentary web of discontinuities in gas density and magnetic field. Through comparison with simulations, we demonstrate that turbulence in the warm ionized medium has a relatively low sonic Mach number, M_s <~ 2. The development of statistical tools for the analysis of polarization gradients will allow accurate determinations of the Mach number, Reynolds number and magnetic field strength in interstellar turbulence over a wide range of conditions.Comment: 5 pages, 3 figures, published in Nature on 13 Oct 201

    Patient satisfaction with hospital care and nurses in England:An observational study

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    ObjectivesTo inform healthcare workforce policy decisions by showing how patient perceptions of hospital care are associated with confidence in nurses and doctors, nurse staffing levels and hospital work environments.DesignCross-sectional surveys of 66 348 hospital patients and 2963 inpatient nurses.SettingPatients surveyed were discharged in 2010 from 161 National Health Service (NHS) trusts in England. Inpatient nurses were surveyed in 2010 in a sample of 46 hospitals in 31 of the same 161 trusts.ParticipantsThe 2010 NHS Survey of Inpatients obtained information from 50% of all patients discharged between June and August. The 2010 RN4CAST England Nurse Survey gathered information from inpatient medical and surgical nurses.Main outcome measuresPatient ratings of their hospital care, their confidence in nurses and doctors and other indicators of their satisfaction. Missed nursing care was treated as both an outcome measure and explanatory factor.ResultsPatients’ perceptions of care are significantly eroded by lack of confidence in either nurses or doctors, and by increases in missed nursing care. The average number of types of missed care was negatively related to six of the eight outcomes—ORs ranged from 0.78 (95% CI 0.68 to 0.90) for excellent care ratings to 0.86 (95% CI 0.77 to 0.95) for medications completely explained—positively associated with higher patient-to-nurse ratios (b=0.15, 95% CI 0.10 to 0.19), and negatively associated with better work environments (b=−0.26, 95% CI −0.48 to −0.04).ConclusionsPatients’ perceptions of hospital care are strongly associated with missed nursing care, which in turn is related to poor professional nurse (RN) staffing and poor hospital work environments. Improving RN staffing in NHS hospitals holds promise for enhancing patient satisfaction.</jats:sec

    The australia telescope compact array HI survey of the galactic center

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    We present a survey of atomic hydrogen (H I) emission in the direction of the Galactic Center (GC) conducted with the CSIRO Australia Telescope Compact Array (ATCA). The survey covers the area -5° ≤ l ≤ +5°, -5° ≤ b ≤ +5° over the velocity range -309 km s -1 ≤ v LSR ≤ 349km s -1 with a velocity resolution of 1km s -1. The ATCA data are supplemented with data from the Parkes Radio Telescope for sensitivity to all angular scales larger than the 145″ angular resolution of the survey. The mean rms brightness temperature across the field is 0.7K, except near (l, b) = 0°, 0° where it increases to ∼2K. This survey complements the Southern Galactic Plane Survey to complete the continuous coverage of the inner Galactic plane in H I at ∼2′ resolution. Here, we describe the observations and analysis of this GC survey and present the final data product. Features such as Bania's Clump2, the far 3kpc arm, and small high-velocity clumps are briefly described

    Estimating the economic cost of nurse sensitive adverse events amongst patients in medical and surgical settings

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    Aims: To identify the costs associated with nurse sensitive adverse events and the impact of these events on patients’ length of stay. Design: Retrospective cohort study using administrative hospital data. Methods: Data were sourced from patient discharge information (N = 5544) from six acute wards within three hospitals (July 2016–October 2017). A retrospective patient record review was undertaken by extracting data from the hospitals’ administrative systems on inpatient discharges, length of stay and diagnoses; eleven adverse events sensitive to nurse staffing were identified within the administrative system. A negative binomial regression is employed to assess the impact of nurse sensitive adverse events on length of stay. Results: Sixteen per cent of the sample (n = 897) had at least one nurse sensitive adverse event during their episode of care. The model revealed when age, gender, admission type and complexity are controlled for, each additional nurse sensitive adverse event experienced by a patient was associated with an increase in the length of stay beyond the national average by 0.48 days (p =.001). Applying this to the daily average cost of inpatient stay per patient (€1456), we estimate the average cost associated with each nurse sensitive adverse event to be €694. Extrapolating this nationally, the economic cost of nurse sensitive adverse events to the health service in Ireland is estimated to be €91.3 million annually. Conclusion: These potentially avoidable events are associated with a significant economic burden to health systems. The estimates provided here can be used to inform and prepare the way for future economic evaluations of nurse staffing initiatives that aim to improve care and safety. Impact: As many of these nurse sensitive adverse events are avoidable, in addition to patient benefits, there is a potential substantial financial return on investment from strategies such as improved nurse staffing that can reduce their occurrence

    Randomised trial of glutamine and selenium supplemented parenteral nutrition for critically ill patients

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    Background: Mortality rates in the Intensive Care Unit and subsequent hospital mortality rates in the UK remain high. Infections in Intensive Care are associated with a 2–3 times increased risk of death. It is thought that under conditions of severe metabolic stress glutamine becomes "conditionally essential". Selenium is an essential trace element that has antioxidant and anti-inflammatory properties. Approximately 23% of patients in Intensive Care require parenteral nutrition and glutamine and selenium are either absent or present in low amounts. Both glutamine and selenium have the potential to influence the immune system through independent biochemical pathways. Systematic reviews suggest that supplementing parenteral nutrition in critical illness with glutamine or selenium may reduce infections and mortality. Pilot data has shown that more than 50% of participants developed infections, typically resistant organisms. We are powered to show definitively whether supplementation of PN with either glutamine or selenium is effective at reducing new infections in critically ill patients. Methods/design: 2 × 2 factorial, pragmatic, multicentre, double-blind, randomised controlled trial. The trial has an enrolment target of 500 patients. Inclusion criteria include: expected to be in critical care for at least 48 hours, aged 16 years or over, patients who require parenteral nutrition and are expected to have at least half their daily nutritional requirements given by that route. Allocation is to one of four iso-caloric, iso-nitrogenous groups: glutamine, selenium, both glutamine & selenium or no additional glutamine or selenium. Trial supplementation is given for up to seven days on the Intensive Care Unit and subsequent wards if practicable. The primary outcomes are episodes of infection in the 14 days after starting trial nutrition and mortality. Secondary outcomes include antibiotic usage, length of hospital stay, quality of life and cost-effectiveness. Discussion: To date more than 285 patients have been recruited to the trial from 10 sites in Scotland. Recruitment is due to finish in August 2008 with a further six months follow up. We expect to report the results of the trial in summer 2009. Trial registration: This trial is registered with the International Standard Randomised Controlled Trial Number system. ISRCTN87144826Not peer reviewedPublisher PD
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